1. Field of the Invention
This invention relates to a generator, and more particularly to a generator having the function of automatically adapting itself to parallel operation of a plurality of generators connected in parallel with each other by automatically synchronizing the phases of outputs from the generators.
2. Prior Art
When a plurality of generators connected in parallel with each other are in operation, if the output voltages from the generators are not synchronous with each other, there occurs a difference between the output voltages. This causes a flow of electric current from one generator into another generator, which can result in an excessive amount of current flowing in the one generator. In the worst case, it may destroy component parts thereof. Therefore, it is required to synchronize the output voltages from the generators during parallel operation.
This, however, necessitates providing wiring for transmitting signals for informing each other of operating conditions thereof, even in the case of parallel operation of identically-constructed generators. Alternatively, as disclosed e.g. in Japanese Patent Publication (Kokoku) No. 56-20782, it necessitates employing an automatic synchronizing device and means for producing an operating point at which the phase coincides with each other to cause the automatic synchronizing device to reliably operate shortly after the start thereof. Another solution is to employ a special adaptor for parallel operation of two generators, with one of them serving as a master generator while the other as a slave generator, as disclosed in Japanese Provisional Utility Model Publication (Kokai) No. 62-145440.